JP7334568B2 - Heating device, liquid ejection device - Google Patents

Description

The present invention relates to a heating device and a device for ejecting liquid.

2. Description of the Related Art Among apparatuses having means for ejecting liquid, there are some that have a heating device that heats a sheet material (applied member) to which liquid is applied.

For example, there is a method in which a sheet material is heated and dried while being conveyed by a suction conveying belt (Patent Document 1).

JP 2018-154500 A

By the way, when the sheet material is heated while being conveyed by the suction conveying belt, the temperature becomes relatively high in the portion without the suction holes, and the temperature does not rise relatively in the portion with the suction holes, resulting in temperature unevenness. There is a problem that image unevenness such as color unevenness occurs in the image of the liquid applied to the sheet material due to the temperature unevenness of the suction conveying belt.

The present invention has been made in view of the above problems, and an object of the present invention is to suppress the occurrence of image unevenness.

In order to solve the above problems, the heating device according to claim 1 of the present invention includes:
a suction conveyor belt that sucks the received sheet material and conveys the sheet material by circular movement;
and heating means for heating the sheet material conveyed by the suction conveying belt,
means for cooling the suction and conveyance belt between a position where heating by the heating means is completed and a position where the sheet material is received in the rotation direction of the suction and conveyance belt ;
The means for cooling is first suction means for sucking from the suction holes of the suction conveying belt from a position where the sheet material is received until heating by the heating means is started,
An air current generated by the suction by the first suction means is applied between a position on the suction conveying belt where heating by the heating means is completed and a position for receiving the sheet material.
It was configured.

According to the present invention, image unevenness can be suppressed.

1 is a schematic explanatory diagram of a printing device that is a device that ejects liquid according to a first embodiment of the present invention; FIG. It is front explanatory drawing of the circumference|surroundings of the drying part in the same 1st Embodiment. It is also a side cross-sectional explanatory view. 1 is a perspective explanatory view of a first example of a suction conveying belt; FIG. 1 is a perspective explanatory view of a first example of a suction conveying belt; FIG. It is front explanatory drawing of the circumference|surroundings of the drying part in 2nd Embodiment of this invention. It is also a side cross-sectional explanatory view. FIG. 4 is an explanatory plan view for explaining an opening of a duct of the belt cooling means; It is front explanatory drawing of the circumference|surroundings of the drying part in 3rd Embodiment of this invention. FIG. 11 is a block explanatory diagram of a part related to air volume control in the fourth embodiment of the present invention; It is explanatory drawing of an example of the table stored in the memory|storage means. FIG. 4 is a flow chart for explaining air volume control in the same embodiment; FIG. 11 is a flow diagram for explaining air volume control in a fifth embodiment of the present invention; FIG. 11 is a schematic explanatory diagram of a printing apparatus according to a sixth embodiment of the present invention; It is a block explanatory diagram of a part related to air volume control in the same embodiment. It is explanatory drawing of an example of the table stored in the memory|storage means. FIG. 4 is a flow chart for explaining air volume control in the same embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. First, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is a schematic explanatory diagram of a printing apparatus, which is an apparatus for ejecting liquid, according to the embodiment.

The printing apparatus 1 includes a loading section 100 , a printing section 200 , a drying section 300 and an unloading section 400 . In the printing apparatus 1, the printing unit 200 applies liquid to the sheet material P carried in from the carrying-in unit 100 to perform required printing, and the drying unit 300, which is the drying apparatus according to the present invention, attaches the liquid to the sheet material P. After drying the liquid, the sheet material P is discharged to the carry-out section 400 .

The carry-in unit 100 includes a carry-in tray 110 on which a plurality of sheet materials P are stacked, a feeding device 120 that separates and feeds the sheet materials P one by one from the carry-in tray 110, and a register that feeds the sheet materials P to the printing unit 200. A roller pair 130 is provided.

As the feeding device 120, any feeding device can be used, such as a device using rollers, a device using air suction, or the like. After the leading edge of the sheet material P delivered from the carry-in tray 110 by the feeding device 120 reaches the registration roller pair 130, the registration roller pair 130 is driven at a predetermined timing to deliver the sheet material P to the printing unit 200.

The printing unit 200 includes a carrier drum 210, which is a rotating body that carries and conveys the sheet material P on its outer peripheral surface, and means for applying liquid that ejects liquid toward the sheet material P carried by the carrier drum 210. and a liquid ejection part 220 . The printing unit 200 also includes a transfer drum 201 that receives the fed sheet material P and transfers it to the carrier drum 210 , and a transfer drum 202 that transfers the sheet material P conveyed by the carrier drum 210 to the drying unit 300 . .

The sheet material P conveyed from the carry-in unit 100 to the printing unit 200 is gripped at the leading end by a sheet gripper provided on the surface of the transfer cylinder 201 and conveyed as the transfer cylinder 201 rotates. The sheet material P conveyed by the transfer drum 201 is transferred to the carrier drum 210 at a position facing the carrier drum 210 .

A sheet gripper is also provided on the surface of the carrier drum 210, and the leading edge of the sheet material P is gripped by the sheet gripper. A plurality of suction holes are dispersedly formed on the surface of the carrier drum 210 , and a suction device 211 generates a suction airflow toward the inside of the carrier drum 210 in each of the suction holes.

The sheet material P transferred from the transfer drum 201 to the carrier drum 210 is gripped by the sheet gripper at the leading end, and is attracted to the surface of the carrier drum 210 by the suction air current, and is conveyed as the carrier drum 210 rotates. be done.

The liquid ejection section 220 includes ejection units 230 (230A to 230F) that are liquid applying means. For example, the ejection unit 230A uses cyan (C) liquid, the ejection unit 230B uses magenta (M) liquid, the ejection unit 230C uses yellow (Y) liquid, and the ejection unit 230D uses black (K) liquid. Dispense each. Also, the ejection units 230E and 230F are used to eject either YMCK or special liquid such as white or gold (silver). Furthermore, a discharge unit for discharging a processing liquid such as a surface coating liquid may be provided.

The ejection operations of the ejection units 230A to 230F of the liquid ejection section 220 are controlled by drive signals corresponding to print information. When the sheet material P carried by the carrying drum 210 passes through the area facing the liquid ejection section 220, the liquid of each color is ejected from the ejection units 230A to 230F, and an image corresponding to the print information is printed.

The sheet material P to which the liquid has been applied by the liquid ejector 220 is delivered from the surface of the carrier drum 210 to the transfer cylinder 202 which is a transfer rotating body. A gripping means (gripper) for gripping the leading edge of the sheet material P is also provided on the surface of the transfer cylinder 202, and the gripping of the leading edge of the sheet material P is changed from the gripper of the carrier drum 210 to the gripper of the transfer cylinder 202. As a result, the sheet material P is transferred from the surface of the carrier drum 210 to the transfer cylinder 202 .

As the transfer drum 202 rotates, the sheet material P is transferred to the suction conveying means 310 of the drying section 300 through the peripheral surface (transfer path) of the transfer drum 202 .

A first heating means 330 is arranged between the printing unit 200 and the drying unit 300 to heat the sheet material P in the transfer path of the transfer cylinder 202 , and the liquid adhering to the sheet material P in the printing unit 200 is heated. is heated by the first heating means 330 .

The drying section 300 includes a heating device 301 according to the present invention, and the sheet material P to which the liquid has been applied by the printing section 200 is dried (pre-dried) by the first heating means 330, and then heated by the transfer cylinder 202. It is transferred to the device 301 and further heat-treated by the heating device 301 .

As a result, liquid components such as moisture in the liquid evaporate, the coloring agent contained in the liquid is reliably fixed on the sheet material P, and curling of the sheet material P is suppressed.

The carry-out section 400 includes a carry-out tray 410 on which a plurality of sheet materials P are stacked. The sheet materials P conveyed from the drying section 300 are sequentially stacked and held on the carry-out tray 410 .

As a device for ejecting liquid, a printing device for printing on a cut sheet material P is described, but the present invention is similarly applied to a printing device for printing on a continuous body such as continuous paper. can.

Here, ink as a liquid used in the printing apparatus 1 will be described.

The ink of this embodiment is a water-based ink containing an organic solvent, water, a coloring material, a resin, and an additive.

<Ink>
Organic solvents, water, coloring materials, resins, additives, and the like used in the ink are described below.
<Organic solvent>
The organic solvent used in the present invention is not particularly limited, and any water-soluble organic solvent can be used. Examples thereof include polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, and sulfur-containing compounds.

It is preferable to use an organic solvent having a boiling point of 250° C. or less because it not only functions as a wetting agent but also provides good drying properties.

The content of the organic solvent in the ink is not particularly limited and can be appropriately selected according to the purpose. 20% by mass or more and 60% by mass or less is more preferable.

<Water>
The content of water in the ink is not particularly limited and can be appropriately selected according to the purpose. % or more and 60 mass % or less is more preferable.

<Color material>
The coloring material is not particularly limited, and pigments and dyes can be used.

An inorganic pigment or an organic pigment can be used as the pigment. These may be used individually by 1 type, and may use 2 or more types together. Mixed crystals may also be used as pigments.

The content of the coloring material in the ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass, from the viewpoints of improving image density, good fixability, and ejection stability. It is below.

Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy color pigments such as gold and silver, and metallic pigments.

<Resin>
The type of resin contained in the ink is not particularly limited and can be appropriately selected according to the purpose. resins, styrene-butadiene-based resins, vinyl chloride-based resins, acrylic-styrene-based resins, acrylic-silicone-based resins, and the like.

The content of the resin is not particularly limited and can be appropriately selected according to the purpose. However, from the viewpoint of fixability and storage stability of the ink, the content is 1% by mass or more and 30% by mass or less based on the total amount of the ink. is preferable, and 5% by mass or more and 20% by mass or less is more preferable.

<Additive>
Surfactants, antifoaming agents, antiseptic antifungal agents, anticorrosive agents, pH adjusters, etc. may be added to the ink as necessary.

Next, the first heating means in the first embodiment of the present invention and the heating apparatus according to the present invention will be described with reference to FIGS. 2 and 3. FIG. FIG. 2 is a front explanatory view of the periphery of the drying section, and FIG. 2 is a side sectional explanatory view of the same.

In this embodiment, an infrared heater (IR heater) 330A capable of radiant heat transfer and a blower 330B are arranged as the first heating means 330 inside the transfer drum 202 . Further, an infrared heater 330C capable of radiant heat transfer is arranged outside the transfer cylinder 202. As shown in FIG.

The heating device 301 includes suction conveying means 310 that conveys (sucks and conveys) the sheet material P transferred from the transfer cylinder 201 of the printing unit 200 in a suction state, and heats the sheet material P that is conveyed by the suction conveying means 310 . and a second heating means 320 . The heating device 301 also includes a belt cooling means 500 for cooling the suction conveying means 310 .

The suction conveying means 310 includes a suction conveying belt 311 that sucks (sucks) and conveys the sheet material P transferred from the transfer drum 202 . The suction conveying belt 311 is looped between a driving roller 313 as a driving rotating body and a driven roller 314 as a driven rotating body, and is rotated by driving the driving roller 313 .

The suction conveying belt 311 has a ventilation structure in which a plurality of through holes (suction holes) are distributed and opened on its surface.

Inside the suction conveying belt 311, a first suction means 315 including one or a plurality of suction fans on the upstream side as a suction mechanism and a second suction means 315 including one or a plurality of suction fans on the downstream side are provided. 316 are arranged. The first suction unit 315 and the second suction unit 316 can also be configured by combining a common suction fan and a plurality of suction ducts.

By operating the first suction means 315 and the second suction means 316 , suction is performed from the plurality of suction holes of the suction conveying belt 311 , and the sheet material P is attracted to the suction conveying belt 311 .

For the suction conveying belt 311, for example, a glass fiber mesh belt can be used. The mesh belt is formed by arranging linear members in a mesh pattern, as shown in the first example of FIG. 4, for example. By using the mesh belt, it is possible to reduce fluttering of the sheet material P due to rebounding of hot air blown by the air blowing means 322 and the heating means 321 .

It should be noted that the suction conveying belt 311 may have suction holes formed on its surface, and as shown in the second example of FIG. It may be a bulk member. Moreover, the shape of the suction hole is not limited to the rectangular shape shown in FIGS. 4 and 5, and may be circular.

The second heating means 320 of the heating device 301 includes a heating means 321 and an air blowing means 322 for drying the liquid on the sheet material P conveyed by the suction conveying belt 311 in the chamber 323 . The second heating means 320 can use radiation heating means, such as an IR heater.

The amount of heat given to the sheet material P by the second heating means 320 is made larger than the total amount of heat given to the sheet material P by the IR heaters 330A and 330C as the first heating means 330. FIG.

Next, the effect of the 1st heating means 330 and the 2nd heating means 320 is demonstrated.

In the present embodiment, IR heaters 330A and 330C and a blower 330B as the first heating means 330 are arranged on the transfer path of the transfer drum 202 for transferring the sheet material P from the carrier drum 210 to the suction transfer belt 311 of the suction transfer means 310. The sheet material P is dried by

Then, the sheet material P dried by the IR heaters 330A and 330C and the air blower 330B is further dried by blowing warm air from the air blowing means 322 and the heating means 321 of the second heating means 320 .

As a result, the liquid applied to the sheet material P can be reliably heated, and the drying property is improved.

That is, by performing heating by the first heating means 330 early before heating by the second heating means 320, drying unevenness and gloss caused by movement of the pigment on the printing surface (surface to which the liquid is applied) are reduced. Unevenness and image unevenness can be suppressed. Then, by performing heating by the second heating means 320 in this state, it is possible to reliably fix the toner and prevent peeling of the printed surface.

Note that the first heating means 330 is not limited to being installed inside or outside the transfer cylinder 202 described above. For example, either the inside or the outside may be used. Similarly, the presence or absence of warm air by air blowing is not limited.

Here, since the suction conveying belt 311 faces the second heating means 320 , the temperature of the belt surface (the surface in contact with the sheet material P) is increased by the air blowing means 322 and the heating means 321 . However, since the intake holes of the suction conveying belt 311 are spaces, the temperature does not rise more than the belt surface.

Therefore, if the sheet material P is put on the belt surface of the suction conveying belt 311 in a state where the water-based liquid (ink) is not very dry, the ink on the sheet material P will be The pigment inside flows, and a pattern (color unevenness) corresponding to the shape of the net of the mesh belt appears in the image. In particular, color unevenness occurs on coated paper (a sheet whose surface is coated with a coating material to increase smoothness) when the sheet material P is thin or has a small basis weight.

Therefore, as in this embodiment, the flow of ink is suppressed by performing heating (pre-drying) by the first heating means before heating (main drying) by the second heating means 320 on the suction conveying belt 311 . Therefore, it is possible to prevent an abnormal image in which traces of the mesh belt appear in the image. That is, when a water-based liquid (ink) is applied to the sheet material P, and the sheet material P is dried while being conveyed by a belt having suction holes such as a mesh belt, the sheet material P is applied to the mesh belt. Abnormal images can be prevented by performing pre-drying before placing.

In addition, since ink containing at least water is used as a liquid as in the present embodiment, heating by the first heating means 330 causes non-uniform heating between the belt surface of the suction conveying belt 311 and the suction holes. It is possible to suppress the flow of the ink and suppress the rubbing of the ink when the sheet materials P are stacked on the carry-out section 400 by heating by the second heating means 320 .

Next, the belt cooling means 500 will be explained.

Here, the area of the suction conveying belt 311 that conveys the sheet material P in the conveying direction Y1 is called a feed portion 311a, and the portion that moves in the opposite direction Y2 to the conveying direction Y1 is called a return portion 311b.

The belt cooling means 500 is located between the outlet 323b (position A) of the chamber 323, which is the position where the heating by the second heating means 320 is completed, and the position B where the sheet material P is received (area At C), the suction conveying belt 311 is cooled.

In this embodiment, the belt cooling means 500 sucks from the suction holes of the suction conveying belt 311 arranged between the position B and the inlet 323a (position E) of the chamber 323 of the second heating means 320 (region D). It is composed of a first suction means 315 for performing

The first suction unit 315 has a gap with respect to the suction conveying belt 311 and is arranged at a position that does not interfere with the circular movement of the suction conveying belt 311 . In addition, the first suction unit 315 keeps the gap between the suction and conveyance belt 311 even when the suction holes of the suction and conveyance belt 311 are blocked by the sheet material P, that is, even when the sheet P is attracted to the suction and conveyance belt 311 . By performing suction through a suction hole that is not blocked by the sheet material P, the air can be blown.

In this manner, the return portion 311b of the suction conveying belt 311 is cooled by the airflow a on the exhaust side generated by the operation of the first suction means 315. As shown in FIG.

In other words, as described above, color unevenness occurs due to the temperature difference between the belt surface of the suction conveying belt 311 and the intake holes. By suppressing this temperature difference, it becomes difficult for the pigment in the ink to flow, and it becomes possible to suppress the amount of heat for preheating.

Therefore, by cooling the return portion 311b of the suction-conveying belt 311 with the airflow a generated by the suction of the first suction means 315, when the sheet material P is transferred onto the suction-conveying belt 311, the belt surface and the air intake holes are cooled. less temperature difference between

As a result, it is possible to suppress the flow of the pigment in the ink, suppress the amount of heat required for pre-drying, and prevent the occurrence of color unevenness.

Further, in the present embodiment, in the area facing the second heating means 320, a space between the second suction means 316 for sucking from the suction holes of the feeding portion 311a of the suction and conveying belt 311 and the return portion 311b of the suction and conveying belt 311 is provided. A shielding wall 502, which is a shielding member for shielding, is arranged.

The inside of the shielding wall 502 communicates with the outside of the heating device 301 through an exhaust path 503 arranged on the rear side of the heating device 301 .

With this configuration, the air warmed by the second heating means 320 is sucked by the second suction means 316, hits the return portion 311b of the suction conveying belt 311 from the exhaust side, and the suction conveying belt 311 reaches the return portion 311b. It is possible to prevent the temperature from rising.

Next, a second embodiment of the invention will be described with reference to FIGS. 6 to 8. FIG. 6 is a front explanatory view of the surroundings of the drying section in the same embodiment, FIG. 7 is a side sectional explanatory view of the same, and FIG. 8 is a plan explanatory view for explaining the opening of the duct of the belt cooling means.

In this embodiment, the belt cooling means 500 comprises a duct 501 that guides the air flow a from the first suction means 315 to the return portion 311b of the suction conveying belt 311. As shown in FIG. The duct 501 allows the airflow a to go around to below the second heating means 320 .

As a result, the suctioned air (airflow a) by the first suction means 315 arranged in the area D can be blown over a wide range of the area C, and efficient cooling can be achieved.

Here, an opening member 511 is provided on the outlet side of the duct 501 . The opening member 511 of the duct 501 has a large number of opening holes 512 (512a to 512c) as shown in FIG. Here, the opening areas of the opening holes 512a, 512b, and 512c are increased in order such that the opening area of the opening holes 512 increases toward the downstream side in the transport direction Y1.

As a result, the air sucked (airflow a) by the first sucking means 315 arranged in the area D can be evenly blown farther, and efficient cooling can be achieved.

Further, an exhaust duct 504 is arranged to face the duct 501 with the suction conveying belt 311 interposed therebetween. The inside of the exhaust duct 504 communicates with the outside through a cool air exhaust path 505 provided on the back side of the heating device 301 .

Here, an opening member 511 is provided on the outlet side of the duct 501 . The opening member 511 of the duct 501 has a large number of opening holes 512 (512a to 512c) as shown in FIG.

Since the space between the duct 501 and the second heating means 320 is shielded by the shielding wall 502 described in the first embodiment, the airflow a flowing in the duct 501 is heated by the second heating means 320. It is prevented that the temperature is raised by hot air.

Next, a third embodiment of the invention will be described with reference to FIG. FIG. 9 is an explanatory front view of the periphery of the drying section in the same embodiment.

In this embodiment, the driving roller 313 and the driven roller 314 (either one of them may be used) around which the suction conveying belt 311 is wound are used as the belt cooling means 500 . In this embodiment, although the first suction means 315 described in the first embodiment is not used together, the first suction means 315 may be used together.

The drive roller 313 and the driven roller 314 (either one of them may be used) are hollow rotating bodies (hollow rollers). is cooled, and the suction conveying belt 311 is cooled.

The suction conveying belt 311 is in contact with the drive roller 313 and the driven roller 314, and heat can be directly transferred, so that the suction conveying belt 311 can be easily cooled.

In this embodiment as well, the returning portion 311b of the suction conveying belt 311 is cooled by the drive roller 313 and the driven roller 314, so that when the sheet material P is transferred onto the suction conveying belt 311, the belt surface and the suction holes temperature difference is reduced.

As a result, it is possible to suppress the flow of the pigment in the ink, suppress the amount of heat required for pre-drying, and prevent the occurrence of color unevenness.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. 10 and 11. FIG. FIG. 10 is a block explanatory diagram of a portion related to air volume control in the same embodiment, and FIG. 11 is an explanatory diagram of an example of a table stored in a storage means.

Here, an example in which the belt cooling means 500 has the configuration of the third embodiment and the air blower 506 is controlled will be described. If the suction amount of the first suction unit 315 is changed without affecting the suction of the sheet material P, the first suction unit 315 of the first and second embodiments can be used instead of the air blower 506 . (The same applies below.).

The control means 801 is a means for controlling the blowing volume (air volume) of the blower 506 .

An operation unit 802 is an operation panel (operation screen) provided in the printing apparatus 1, and inputs the type of the sheet material P (coated paper, plain paper, etc.). The operation unit 802 may be an operation screen of a print instruction terminal (for example, computer) connected to the printing apparatus 1 .

In the storage unit 803, for example, as shown in FIG. 11, the relationship between the information on the type of sheet material P, basis weight or thickness and the air volume of the air blower 506 is stored as a table.

Therefore, the control means 801 reads the air volume information corresponding to the type information of the sheet material P instructed by the operation section 802 from the storage means 803, and controls the air volume of the blower 506 according to the read air volume information.

Next, air volume control in this embodiment will be described with reference to the flowchart of FIG. 12 .

First, the operator sets the type of sheet material P using the operation unit 802 (step S1, hereinafter simply referred to as "S1").

Then, it is determined whether or not the type of sheet material P to be set is plain paper (S2).

Here, if the sheet material P is not plain paper, that is, if the sheet material P is coated paper in the present embodiment, the operator is prompted to set the thickness (or basis weight) of the sheet material P. The thickness (or basis weight) of the sheet material P is set (S3).

Thereafter, it is determined whether or not the set sheet material P is thin paper (S4).

Then, when the sheet material P is thin coated paper, the air volume (cooling air volume) of the blower 506 is increased (S5).

On the other hand, when the sheet material P is plain paper, or when the sheet material P is coated paper and thick paper, the air volume (cooling air volume) of the blower 506 is decreased (S6).

In this manner, when the sheet material does not cause color unevenness due to the influence of uneven heating, the amount of blown air is controlled to be small, so the power consumption of the apparatus can be suppressed.

Note that when the basis weight of the sheet material P exceeds 150 gsm, the basis weight is considered to be large. Usually, it is often managed by the basis weight, but if the thickness is used as a reference, it is also possible to classify the thickness as cardboard if the thickness exceeds 0.17 mm.

Next, a fifth embodiment of the present invention will be described with reference to FIG. FIG. 13 is a flowchart for explaining air volume control in the same embodiment.

In this embodiment, the type number of the sheet material P, the type of the sheet material P, and the grammage (thickness) are associated and stored in the storage unit 803 .

Therefore, the operator inputs the type number of the sheet material P through the operation unit 802 (S11).

Then, it is determined whether or not the type of the input sheet material P is plain paper (S12).

Here, if the sheet material P is not plain paper, that is, if the sheet material P is coated paper in this embodiment, the thickness (or basis weight) of the sheet material P is set (S13).

Thereafter, it is determined whether or not the set sheet material P is thin paper (S14).

Then, when the sheet material P is coated paper and thin paper, the air volume (cooling air volume) of the air blower 506 is increased (S15).

On the other hand, when the sheet material P is plain paper, or when the sheet material P is coated paper and thick paper, the air volume (cooling air volume) of the blower 506 is decreased (S16).

Since the input of the sheet material P is simple in this way, the operability is improved.

Next, a sixth embodiment of the present invention will be described with reference to FIG. FIG. 14 is a schematic explanatory diagram of the printing apparatus 1 according to the embodiment.

In addition to the configuration of the printing apparatus 1 of the first embodiment, the printing apparatus 1 has a preprocessing section 700 that performs preprocessing on the sheet material P, and is arranged upstream of the printing section 200 in the transport path.

The pre-processing unit 700 includes a processing liquid container 705 that stores the processing liquid 704 , a drawing roller 701 that draws up the processing liquid 704 , a coating roller 702 that applies (applies) the processing liquid 704 to the sheet material P, and a coating roller 702 . and a facing roller 703 facing each other with the sheet material P interposed therebetween. Examples of the treatment liquid 704 include a treatment liquid that reacts with liquid to suppress bleeding.

After the application roller 702 applies the treatment liquid 704 to the lower surface of the sheet material P, the sheet material P is turned upside down and conveyed to the registration roller pair 130 . The sheet material P that has passed through the registration roller pair 130 is conveyed so that the surface to which the treatment liquid 704 is applied faces the ejection unit 230 , and the liquid is applied from the ejection unit 230 .

Next, a portion related to air volume control in this embodiment will be described with reference to FIGS. 15 and 16. FIG. FIG. 15 is a block explanatory diagram of a portion related to the same air volume control, and FIG. 16 is an explanatory diagram of an example of a table stored in the storage means.

In the present embodiment, as shown in FIG. 16, the storage unit 803 stores information on the type of sheet material P, basis weight or thickness, and the air volume of the air blower 506, including the relationship with the presence or absence of application of the treatment liquid. are stored as a table. Further, as in the fifth embodiment, the type number of the sheet material P, the type of the sheet material P, and the basis weight (thickness) are associated and stored.

Information on the presence or absence of application is also input to the control means 801 from the pretreatment unit 700 .

Therefore, the control means 801 reads from the storage means 803 the air volume information corresponding to the type number information of the sheet material P instructed by the operation section 802, and controls the air volume of the blower 506 according to the read air volume information.

Next, air volume control in this embodiment will be described with reference to the flowchart of FIG. 17 .

When the operator sets whether or not to apply the treatment liquid, information regarding the setting of whether or not to apply the treatment liquid is input from the preprocessing unit 700 (S21). After that, the type number of the sheet material P is input through the operation unit 802 (S23).

Then, it is determined whether or not the treatment liquid is applied (S23).

Here, if the treatment liquid is not applied, it is determined whether or not the sheet material P is thin coated paper (S24).

Then, when the sheet material P is thin coated paper, the air volume (cooling air volume) of the air blower 506 is increased (S25).

On the other hand, when the treatment liquid is applied or when the sheet material P is not thin coated paper, that is, when it is thick coated paper, the air volume (cooling air volume) of the blower 506 is reduced (S26).

In other words, the effect of preventing the flow of ink by heating the first heating means 330 has been described above, but there is a correlation between the flow of ink and the presence or absence of application of the treatment liquid. , the treatment liquid can prevent the flow of the ink pigment.

However, since the application of the treatment liquid increases the cost of the printed matter, it is preferable to select whether or not to apply the treatment liquid according to the required output.

Therefore, in this embodiment, whether or not the first heating means 330 performs heating is controlled depending on whether or not the treatment liquid is applied.

When the treatment liquid is applied, it is possible to prevent the flow of the ink pigment due to the temperature of the surface of the suction conveying belt 311 and the suction holes.

In each of the above-described embodiments, an endless belt is used as the rotating body constituting the suction and conveying means, but a drum-like (roller-like) rotating body may be used. In this case, means for cooling the rotating body is arranged between the position where heating by the heating means is completed and the position for receiving the sheet material in the rotating direction of the rotating body.

Reference Signs List 1 printing device 100 loading unit 200 printing unit 230 ejection unit 300 drying unit 310 suction conveying means 311 suction conveying belt 313 drive roller 314 driven roller 315 first suction means 316 second suction means 320 second heating means 330 first heating means 500 Belt cooling means 501 Duct 506 Air blower 700 Pretreatment section

Claims (12)

a suction conveyor belt that sucks the received sheet material and conveys the sheet material by circular movement;
and heating means for heating the sheet material conveyed by the suction conveying belt,
means for cooling the suction and conveyance belt between a position where heating by the heating means is completed and a position where the sheet material is received in the rotation direction of the suction and conveyance belt ;
The means for cooling is first suction means for sucking from the suction holes of the suction conveying belt from a position where the sheet material is received until heating by the heating means is started,
An air current generated by the suction by the first suction means is applied between a position on the suction conveying belt where heating by the heating means is completed and a position for receiving the sheet material.
A heating device characterized by: 2. The apparatus according to claim 1, further comprising a duct that guides an air current generated by suction by said first suction means between a position on said suction conveying belt where heating by said heating means is completed and a position where said sheet material is received. Heating device as described. 3. The heating device according to claim 2 , wherein said duct has an opening hole whose opening area becomes wider on the side away from said first suction means. 4. The heating device according to claim 1 , wherein said cooling means is means for cooling at least one of a driving rotating body and a driven rotating body around which said suction conveying belt is wound. . at least one of the driving rotating body and the driven rotating body is a hollow rotating body;
5. The heating device according to claim 4 , further comprising means for allowing airflow to pass through the interior of said hollow rotor. a suction conveyor belt that sucks the received sheet material and conveys the sheet material by circular movement;
and heating means for heating the sheet material conveyed by the suction conveying belt,
means for cooling the suction and conveyance belt between a position where heating by the heating means is completed and a position where the sheet material is received in the rotation direction of the suction and conveyance belt;
When the region of the suction conveyor belt that conveys the sheet material in the conveying direction is defined as a feed portion, and the region that moves in the direction opposite to the feed portion is defined as a return portion,
A shielding member for shielding between the second suction means for sucking from the suction holes of the feeding portion of the suction/conveyance belt and the return portion of the suction/conveyance belt is disposed in a region facing the heating means. A heating device characterized by: a suction conveyor belt that sucks the received sheet material and conveys the sheet material by circular movement;
and heating means for heating the sheet material conveyed by the suction conveying belt,
means for cooling the suction and conveyance belt between a position where heating by the heating means is completed and a position where the sheet material is received in the rotation direction of the suction and conveyance belt;
The means for cooling is means for cooling by air flow,
The heating device, wherein the thinner the sheet material, the greater the air flow rate. a suction conveyor belt that sucks the received sheet material and conveys the sheet material by circular movement;
and heating means for heating the sheet material conveyed by the suction conveying belt,
means for cooling the suction and conveyance belt between a position where heating by the heating means is completed and a position where the sheet material is received in the rotation direction of the suction and conveyance belt;
The means for cooling is means for cooling by air flow,
The heating device is characterized in that an air flow rate is made smaller when the sheet material is plain paper than when the sheet material is coated paper. a suction conveyor belt that sucks the received sheet material and conveys the sheet material by circular movement;
and heating means for heating the sheet material conveyed by the suction conveying belt,
means for cooling the suction and conveyance belt between a position where heating by the heating means is completed and a position where the sheet material is received in the rotation direction of the suction and conveyance belt;
The means for cooling is means for cooling by air flow,
A heating device, wherein when the treatment liquid is applied to the sheet material, an air flow rate is made smaller than when the treatment liquid is not applied. a rotating body for sucking and conveying the received sheet material;
and heating means for heating the sheet material conveyed by the rotating body,
means for cooling the rotating body between a position where heating by the heating means is completed and a position for receiving the sheet material in the rotating direction of the rotating body ;
The means for cooling is first suction means for sucking from the suction holes of the rotating body from a position where the sheet material is received until heating by the heating means is started,
An air current generated by suction by the first suction means is applied between a position of the rotating body where heating by the heating means is completed and a position for receiving the sheet material.
A heating device characterized by: A drying apparatus comprising the heating apparatus according to any one of claims 1 to 10. a liquid application means for applying liquid to the sheet material;
A device for ejecting liquid, comprising: the heating device according to any one of claims 1 to 10; or the drying device according to claim 11.

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